Greetings everyone. I don't post much on DT, I mostly hang out on r/MK, and in the Mech Keys discord. I figured I would post this here too, because I think DT is a more tech-savvy community, and might find most appeal here.

I am nearing the stage of starting a Group Buy for the Postage Board. I've named them "postage" because, when mounted underneath a keyboard, they resemble postage stamps on an envelope. I assure you their functionality is cooler than their name

It will help me make the best choices when it comes to how to deliver this board to the community. I want to design the GB in a way that accommodates the majority of the community.

What is a Postage Board?

The Postage Board is a controller board (like a Pro Micro, or a Teensy) that is designed to mount to the bottom of 3x switches on the top row of your hand-wired mechanical keyboard. My goal was to solve many problems/annoyances that go along with making a handwire keyboard.

- The board has a secure home, no glue, 2-side-tape, or other ugly mounting methods- The USB Type-C connector is securely placed on the top edge of the keyboard- The board has an optional location to add a 3.5mm TRRS headphone jack to use if you are making a Split-layout keyboard

Here is a diagram of both boards side-by-side. If you have no interest in split-layout keyboards, you can ignore the Postage Expander. https://i.imgur.com/yRQBj46.png

I've had some delays with getting the correct components delivered to allow me to assemble some prototypes for testing. I should have the components in the next few days, and I hope to be able to show off a working keyboard using the board immediately. When these boards are sold in a GB, the PCBs will not be hand-soldered. They will be fully assembled by a reputable PCB manufacturer in Shenzhen.

What is the Postage Expander?

The Postage Expander is a companion board that would be used as the controller on the "slave" side of a split keyboard layout. This allows you to make a split keyboard (like the Lets Split, or others) using the main Postage Board (on the Master side), along with the Postage Expander (on the Slave side), for a lower cost than buying 2x Postage Boards. This lower cost was made possible by using an "IO Expander", rather than another Microcontroller, along with not requiring other expensive components like USB. I used the MCP23018 IO Expander, which is the same one used in the Ergodox. If you want to see an example of how firmware is written in QMK for an Atmega32u4 + MCP23018, check out the Ergodox code on Github.

The Postage expander is probably not going to be finished its testing phase by the time of the Postage Board group buy. If anyone is interested in testing out the Expander in its unproven state, reach out to me.